An invert air is an air with your bodyboard and body momentarily in an inverted position. After holding this move for a moment or two, you should untwist yourself in the same direction you twisted.
1. Choose a wave with a steep section and a lip that is going to throw.
2. Make sure that you have plenty of speed and aim at this lip; do not try to hit it vertically , choose an angle that will allow you to land in front of the wave after flying over it.
3. Once you hit the lip, throw your weight up and towards the front of the wave.
4. Tweak your body and bodyboard in an inverted position which means that the bottom of your bodyboard should face the sky and your head should look down where you want to land.
5. Keep this position for about a second or two , then untwist your bodyboard and body in the same direction you twisted, preparing the landing like for a normal air.
6. After landing, re engage you rail for the next move.
This trick can be very spectacular , each bodyboarder has his/her own style , an Invert Air is a good way to express it !